Treatment of fibrous material



Patented Nov. 3, 1931 UNITED STATES.

LEON LILIENFELD, or VIENNA, AUSTRIA TREATMENT OF FIBROUS MATERIAL NoDrawing. Application filed July 25,1927, Serial N 'o. 208,402, and inAustria June 9, 1927.

Difiiculties are associated with the use of viscose or cellulosesolutions as an agent for dressing woven textile materials or sizingyarn, on account of the fact that the fabric 5 or yarn which has beenthus treated acquires a stil'hpaper-like and cold feel, and moreover itsextensibility is rather low. Fabrics which have been dressed by means ofviscose have also the disadvantage that the cellulose regenerated fromthe viscose applied to the fabric frequently undergoes rupture when thematerial is stretched or pulled,

owing to the difference between the coefficients of extensibility of thefabric and the coating, the result being that the coating exhibitsnumerous minute, or more or less coarse, cracks. Even in textileprinting, particularly in pigment printing with viscose se/defects areapparent to an undesi able degree, and the viscose layers printed o thetextile have a stiff feel, and. in many c ses become torn on beingstretched, especially when they are not very thin.

This invention relates to a process for treating textile fibrousmaterial (whether in the form of woven fabrics or of yarn) by dressing,sizing, printing,

like, by means of cellulose in dlssolved form (for example viscose or asolution of cellulose 3 in cuprammonia) from which cellulose can be orprecipitated respectively, foregoing disadvantages are remedied theinvention inwhich can be obregenerated whereby the minimized or eludesalso the products tained by the process.

The invention consists in the application of the discovery that theproperties of the dressing, sizing, printed layers or the like, whichconsist of, or contain, cellulose regenerated from soluble derivativesof cellulose, for example from viscose from a cellulose solution, forexample in cuprammonia, which has been applied to the fibrous material,are improved, especially in respect of feel and extensibility, if thedress-. I ing, sizing or coating contains hollow spaces or bubblesdispersed throughout it, or throughout at least a part of it. These hol-0 lows or bubbles may be produced by dressing, sizing or otherwisetreating the material weighting or the or precipitated with a solutionof a soluble modification of cellulose, for example viscose or with asolution of cellulose, containing a quantity of gas or of a substancecapable of being caused to evolve a gas by a suitable treatment. Thustextile fabrics or yarns which have been dressed, sized or otherwisetreated by means of viscose in accordance with the invention have a softfeel, even when the quantity of the dressing or the like isconsiderable. The dressing is much lighter, and more downy, andtherefore resembles the natural fibre more closely than do the dressingsproduced in the usual manner from viscose'or cellulose solution which isfree from gas, or contains but little gas. Fabrics or yarns treated inaccordance with the invention have also a warm feel, and owing to thehollows in the dressing, sizing or the like, it is possible to produceeven with small proportions of viscose or cellulose solution a" veryfull, rich dressing or sizing. Material treated in accordance with theinvention has a good ca pacity for extension, and fissures or cracks donot occur when the material is pulled or stretched.

The hollow spaces may contain the gas, for example air or carbondioxide, or the gas may be removed, wholly or in part, from them,forexample, by dissolution, or with the aid of an increased or reducedpressure.

In treating fibrous material in accordance with this invention a gas,for example air, hydrogen or nitrogen, may be emulsified in a solutionof a soluble modification of cellulose, for example in crude or purifiedviscose or in a solution of cellulose, for example in cuprammonia, byknown. methods, such as by injection, blowing, beating, agitation or thelike; or the gas may be dissolved in the viscose or other solution withthe aid of pressure. 1

Another method of operating consists in incorporating with the viscoseor solution of cellulose a substance, for example an alkali carbonate,which is capable of evolving gas during the treatment for decomposingthe viscose or precipitating the cellulose with an agent suitable forthe regeneration or precipitation of the viscose respectively.

I The, viscose containing gas or a substance capable of yielding gas isthen applied to or incorporated with a fabric or yarn, by hand, or bymeans of a suitable machine. In order to cause the viscose or cellulosesolution to penetrate more deeply into the fibre, this operation may, ifdesired, be conducted under reduced pressure, or under a raisedpressure. There may be added to the viscose or cellulose solutionanother coating or sizing agent, for

instance, starch, dextrin, albumen or gelatin a softening agent, forinstance, glycerine,

soap, Turkey-red oil, glucose, castor oil, or parafiin oil; a fillingmaterial, for instance, talc or china clay; a pigment, for instance,zinc white, soot, or powdered mica; or a dyestufi', or any two or moreof these substances. I

The cellulose may be regenerated from the viscose or precipitated from'the cellulose solution in any known manner, by a suitable precipitatingbath, or by other means, for instance, by heating, steaming, or merelyby allowing the treated material to stand.

If it is desired to expel the gas, for example air, contained in thehollows in order to permit the walls of the hollows to cellapse, the gasmay be removed for example by boiling with water, or by. treatment withwater under pressure. If the gas contained in the spaces is carbondioxide, it maybe dis solved partly in the precipitating bath, andpartly during the subsequent washing operation.

The following examples illustrate some methods by which the inventionmay be carried into effect, the parts being by weight Example 1.-Air isinjected into a viscose, made 1n any desired manner from matured ornon-matured alkali-cellulose containing I about 5-7 per cent.ofcellulose on analysis, so as to produce an emulsion. A cotton fabricis dressed in known manner in a backfilling machine with the emulsion soproduced, and the dressed material-is treated,

, in the wet state or after drying, by any precipitating bath known inthe viscose art. The material is then washed, dried and finished in theusual manner.

Example 2.-Theprocedi1re is as in Example 1, but with the exception thattale is added to the viscose in quantity amounting to about 23 parts foreach part of cellulose as determined by analysis.

Example 51-100 parts of sulphite-cellulose containing 9-10 per cent. ofmoisture, or 100 parts oflinters containing 7-8 per cent.

of moisture are impregnated at 15 C. with 2,000 parts of a solution ofcaustic soda of 18 per cent. strength. After 3 hours, the soda-celluloseis expressed until its total weight is 300 parts in the case ofsulphitecellulose, or 340 parts in'the case of liuters, and comminutedin a shredding machine for 2 to 3 hours. Before the soda-celluloseresaeoe ture is allowed to react for 8 hours at-15.18

(3.; at the end of this periodany excess of carbon-disulphide which maybe present is removed by blowing through a current of air for about 15minutes, and the cellulose xanthate obtained is dissolved with the aid,

of a quantity of water, caustic soda and sodium carbonate, such that thesolution produced contains 1,220 parts of water, 107 parts of causticsoda and 150 parts otsodium carbonate (reckoned as the anhydroussalt).

A suitable cotton fabric is dressed one or more times in a back-fillingmachine with the viscose produced in the manner just described, afterithas been filteredor strained, and in the freshly prepared state, orafter it has aged for 18-96 hours at 15 C. The dressed material is thenimmediately or after having been dried, then introducedinto sulphuricacid of 10 per cent. strength, or into any other acid precipitating bathknown in the viscose industry, and dried. It will be understood that thematerial may be desulphurized or bleached in any known manner (forexample by means after which it is washed f of a solution of sodiumsulphide) before or after it has been dried.

Ewample .l.-The procedure is as in Example 3, with the exception thatthe alkali cellulose is allowed to stand for a period of 48-70 hours atroom temperature before being treated with carbon disulphide.

Emample 5.-The procedure is as'in Example 3 or Example 4, with theexception that talc is added to the viscose, for example,

from 10 to 30 parts of the tale per parts" of viscose.

Emample 6.The procedure is as in Exits ample 3, Example 4 or Example5,with' the exception that there about 1-2 per cent. of or castor oil.

Ewample 7.The procedure is as in any of the Examples 3-6, with theexception that the is ,added to the viscose its weight of paraifin oilviscose has approximately the composition:

100 parts of parent cellulose, 1,260 parts of water, 67 parts of causticsoda, and 150 parts of sodium carbonate (reckoned as the anhydroussalt).

Ewample 8.--The1 procedure is as in any of the Examples 3-6, with theexception that the viscose has approximately the com sition:

100-parts of parent cellulose, 1,285p rts' of water, 43 parts-of causticsoda and 150 parts 0f1Sdll1m carbonate (reckoned as anhydrous sa t Theviscose as used in any of Examples .3'8 contains about 6.5 to 6.7 percent. of cellulosewhich can be determined by analysis,

sodium carbonate being neglected. There may, however, be used a viscosecontaining a smaller proportion of cellulose, for example, 45 per cent.

Example .9.'10O parts of a viscose containing sodium carbonate as usedin any of Examples 3-8 are intimately mixed with 5-8 parts ogmica orwith v parts of zinc white. cotton material is then printed with thismixture in a Rouleaux machine. The further treatment and finishing areconducted in the manner described in the preceding examples.

Examples for sizing yarn follow from the I foregoing examples.

In carrying out the invention, instead of viscose, there may be used asolution from which cellulose may be precipitated, for example, asolution of cellulose in a thiocyanate solution such as calciumthiocyanate solution, a

solution of cellulose in ammoniacal copper oxide solution, a solution ofcellulose in an aqueous solution of caustic alkali containing urea,thiourea, or guanidine.

Fabrics and/or yarn dressed or sized respectively, with viscose or anycellulose solution, according to the present process, are under themicroscope different from fabrics oryarn filled or sizedaccording to theprocesses known hitherto with viscose or cellulose solutions. Thedifference consists in the following: The small cellulose film particlesthat are on and between the fibres of the fabric or yarn, when producedafter the present process, contain hollow spaces and have consequently aspongy structure, whilst the small cellulose film particles formed onand becording to the processes known heretofore, do not possess thespongy structure characteristicof fabrics and yarn treated after thepresent process. j Even if fabrics and yarn dressed or sizedrespectively, after the processes known hereto ore, with viscose or anycellulose solution have been after-treated on the so-called breakingmachines, the cellulose film particles deposited in or on the fibresshow, under the microscope numerous rents, butnot a spongy structurecharacteristic of fabrics and yarn treated according 'to the presentprocess. j It is to be understood that the term applying to the fibrousmaterial includes any manner of application to the a rial, whether bymanual or mechanical means customary for dressing, sizing, filling,impregnating, coating, weighting or printing a fibrous material, whetherin the state of Woven fabric or in the state of'yarn. The expressionfibrous material in the specification and claims includes.whereverthecontext permits, any spun or woven fibrous material, whether animalor vegetable (for example, flax, linen,. hemp, ramie, jute, wool, andparticularly cotton) in the form of pure fabrics or in the form of mixedfabrics, or in the form of yarn in skeins, cops or warps.

The expression cellulose means in the description and claims: celluloseand its near conversion products, such as cellulose hydrate,hydrocellulose and oxycellulose.

The processes as herein described are claimed in my copendinapplications Serial Number 305,875, filed September 13, 1928, and SerialNumber 393,828, filed September 19, 1929.

The expression precipitated cellulose in the following claims includeswherever the context permits,"regenerated cellulose.

Having thus fully described the nature of my said invention and the bestmeans I know for carrying the same into practical eifect, I claim 1. Asa new product, fibrous material associated with regenerated cellulosewithin which are contained hollow spaces containing at least one gas. v

2. As a new product fibrous material associated with regeneratedcellulose within which are containedhollow spaces containingsubstantially no gas.

3. Cotton material associated with regenerated cellulose within whichare contained hollow spaces, the composite material having an appearanceand feel resentbling those of pure wool material.

4. As a new product, fibrous material carrying cellulose which, underthe microscope, shows numerous hollow spaces.

5. Asa new product, fibrous material carrying cellulose which, under themicroscope, shows a spongy structure.

6. Asa new product, fibrous material carrying precipitated cellulosewhich,-under the microscope, shows numerous hollow spaces.

- 7. As a new product, fibrous material carrying precipitated cellulosewhich, under the microscope, shows a spongy structure.

8. As a new product, fibrous material carryin whic under the microscope,shows numerous hollow spaces.

9. As a new 'roduct, fibrous material carrying on and tween its fibrescellulose which, under the microscope, shows a spongy structure.

10. As a new product, fibrous material carrying on and between itsfibres precipitated cellulose which, under the microscope, showsnumerous hollow spaces.

microscope, show numerous hollow spaces.

1 13. As a new product, fibrous material associated with cellulose filmswhich, under the microscope, show a spongy structure.

14. As a new product, fibrous material associated with films ofprecipitated cellulose on and between its fibres cellulose which, underthe microscope, show numer'-' ous hollow spaces.

15. Asa new roduct, fibrous material associated with s' of precipitatedcellulose I which, under the microscope show a spongy structure.

'16. As a new product, fibrous material associated with films ofcellulose on and between the fibres, which films, under the microsco eshow numerous hollows aces.

As a new product, fibrous material as sociated with of cellulose on end;he-

.tween the fibres, which s, under the mic-. roscope, show a spongystructure. w 18. As a new "product, fibrous material associated withfilms of precipitated cellulose on and between the fibres, which films,under the microscope, show numerous hollowspaces.

19. As a new product, fibrous material :associated with films ofprecipitated cellulose .on and between the fibres, which films, underthe microscope, show a s ongy structure.

In testimony whereo I have signed my name to this specification, 25, DB.LEON LHJIENFELD.

